An outstanding issue with respect to hair colorants includes ease of application and concerns over messy application resulting in skin staining and uneven hair color results. Recent trends indicate that consumers find handling of foamed products preferable to gels, creams or liquids.
Foamed products are known to be generated in one of two ways. The first being the use of a compressed gas (aerosols), which is admixed with a composition that is evacuated from a container by the consumer. A commercial example of this would be Kanebo Cosmetics's Simpro hair colorant. GB2188257A discusses a device for dispensing a two-component product, such as shampoos or dyes in a pressurized container and dispensed in the form of foam.
Outstanding issues with pressurized systems such as these examples include that oxidative hair colorants are radically initiated reactions that require sequestration from oxygen or segregation of the developer from the tint components (couplers, primaries, etc.) until use of the hair colorant is desired by the consumer. A consumer is unable to mix the developer and tint components and maintain a pressurized system therefore the mixing of the components must be done by the dispenser or be per-mixed and sequestered from oxygen by the dispenser. Control of the ratio of tint components to developer components is poor from dispensers that segregate the components right before dispensing. Additionally, it is difficult to product a cost-effective package that can keep an oxidative hair colorant sequestered from oxygen. Therefore, packaging and stability of the oxidative hair colorant composition tend to cause issues for aerosol products.
The second way to generate a foam product is via a non-pressurized dispenser in the form of a pump foamer or squeeze foamer. A commercial example of a pump foamer would be Youngrace Bubble Hair Color product. A commercial example of a squeeze foamer would be Kao's Prettia Soft Foam Color, Liese Bubble Hair Color or Blaune Foam Color products. See also US 2004/0213752A1. Further, U.S. Pat. No. 7,040,507 discusses a foam-type hair dye apparatus for converting a liquid hair dye into foam.
Pump foamers can be difficult to utilize with oxidative hair colorant composition due to the use of metal parts, such as springs, that are exposed to the composition. The high pH of the oxidizing hair coloring composition and presence of an oxidizing agent react with metal parts of the pump mechanism, such as springs, causing damage to the pump foamer and contaminate the composition with oxidized metal ions.
Outstanding issues with squeeze foamers can include poor foam results when the consumer mixes the developer composition and tint composition together to form an oxidative hair colorant composition. See WO 2008/136433 A1. The presence of foam in the headspace can change the quality of the foam to be liquid-like and undesired by consumers.
Therefore, it is a desire to provide an oxidative hair colorant product having a liquid oxidative hair colorant composition in a manually-actuable, non-aerosol dispenser. It is desired that the product allows for vigorous shaking by consumers before dispensing while delivering an acceptable foam and acceptable hair coloring results. Further, there exists a further desire to minimize damage to hair when using oxidative hair coloring products.
It has been found that the reduction of surfactants from the oxidative hair coloring composition can address the outstanding needs of such products and provide further desired benefits.
It has been found that having a particular rheological profile of the oxidative hair coloring composition reduces messy application issues.